An Irish school has strenuously denied that an explicit video featured their teachers or was filmed on school grounds.

Antrim Grammar School released the statement today after an x-rated video was widely shared on social media.

The clip is understood to show two adults engaging in sexual activity in what appears to be a classroom.

Antrim Grammar School shared a statement on Facebook this afternoon and through email with parents saying that their teaching staff weren't the people featured in the footage, which they also said was not filmed on school property.

A spokesperson wrote: "I am writing to you in relation to a video circulating on social media site Facebook purported to have been filmed in Antrim Grammar School and featuring staff from the school.

"I would like to state categorically that the video was not filmed in Antrim Grammar School, does not feature any staff pas or present from Antrim Grammar School, and indeed has absolutely no connection with the school whatsoever."